Use the recycle bin feature to restore deleted NAS data - Container Service for Kubernetes

Container Network File System (CNFS) supports the Recycle Bin feature for restoring accidentally deleted files from File Storage NAS volumes. This tutorial demonstrates the full workflow: deploy an NGINX application backed by a CNFS-managed NAS volume, delete a file to simulate data loss, and restore it from the Recycle Bin.

Billing

Enabling the Recycle Bin is free. However, files in the Recycle Bin consume storage space and are billed at the rate of their original storage type. Specify a retention period to reduce costs. For details, see Billing of General-purpose NAS file systems and Billing of the IA storage class.

Permissions

Only the file system owner or authorized Resource Access Management (RAM) users can use the Recycle Bin. For details, see Perform access control based on RAM policies.

Prerequisites

A cluster that uses CNFS to manage NAS file systems. For details, see Use CNFS to manage NAS file systems.
Internet access enabled for the cluster API server. For details, see Enable Internet access for the API server.
Container Storage Interface (CSI) components that meet the following minimum version requirements:
Component Minimum version Reference
csi-plugin and csi-provisioner 1.20.5-ff6490f-aliyun Update csi-plugin and csi-provisioner
storage-operator 1.18.8.56-2aa33ba-aliyun Manage the storage-operator component

Component	Minimum version	Reference
`csi-plugin` and `csi-provisioner`	1.20.5-ff6490f-aliyun	Update csi-plugin and csi-provisioner
`storage-operator`	1.18.8.56-2aa33ba-aliyun	Manage the storage-operator component

Step 1: Deploy the NGINX application with a CNFS-managed NAS volume

Create a persistent volume claim (PVC), a Deployment, and a LoadBalancer Service. Then write an index.html file to the NAS volume and verify access through a browser.

Verify the CNFS object status

List the CNFS objects in your cluster: Expected output:

   kubectl get cnfs

   NAME                                      AGE
   default-cnfs-nas-7938cef-20210907193713   21h

Check the status of the CNFS object: Expected output: The CNFS object must be in the Available state before you proceed.
```
   kubectl get cnfs default-cnfs-nas-7938cef-20210907193713 -o yaml | grep Available
```
```
   status: Available
```

Create a PVC

Run the following command to create a PVC named cnfs-nas-pvc that references the alibabacloud-cnfs-nas StorageClass:

Important

The storageClassName field must reference a CNFS StorageClass.

cat << EOF | kubectl apply -f -
kind: PersistentVolumeClaim
apiVersion: v1
metadata:
  name: cnfs-nas-pvc
spec:
  accessModes:
    - ReadWriteMany
  storageClassName: alibabacloud-cnfs-nas
  resources:
    requests:
      storage: 30Gi
EOF

Create a Deployment

Run the following command to create a Deployment named cnfs-nas-deployment. The Deployment mounts the PVC to /app and exposes container port 8080 (named http):

Important

The Deployment references the PVC created in the previous step.

cat << EOF | kubectl apply -f -
apiVersion: apps/v1
kind: Deployment
metadata:
  name: cnfs-nas-deployment
  labels:
    app: nginx
spec:
  selector:
    matchLabels:
      app: nginx
  template:
    metadata:
      labels:
        app: nginx
    spec:
      securityContext:
        runAsUser: 0
      containers:
      - name: nginx
        image: docker.io/bitnami/nginx:1.16.1-debian-9-r56
        volumeMounts:
        - mountPath: "/app"
          name: cnfs-nas-pvc
        ports:
        - containerPort: 8080
          name: http
      volumes:
      - name: cnfs-nas-pvc
        persistentVolumeClaim:
          claimName: cnfs-nas-pvc
EOF

Create a LoadBalancer Service

Run the following command to create a LoadBalancer Service named nginx-default. A Server Load Balancer (SLB) instance exposes the Service through a public IP address and forwards HTTP requests to pods with the app: nginx label:

cat << EOF | kubectl apply -f -
apiVersion: v1
kind: Service
metadata:
  name: nginx-default
  labels:
    app: nginx
spec:
  type: LoadBalancer
  externalTrafficPolicy: "Cluster"
  ports:
    - name: http
      port: 80
      targetPort: http
  selector:
    app: nginx
EOF

Write the NGINX welcome page

Get the pod name: Expected output:

   kubectl get pod

   NAME                                   READY   STATUS    RESTARTS   AGE
   cnfs-nas-deployment-597bc9fb45-cmkss   1/1     Running   0          3h23m

Open a shell in the pod and navigate to /app:

   kubectl exec cnfs-nas-deployment-597bc9fb45-cmkss -ti sh
   cd /app

Write the index.html file:

   cat << EOF >> index.html
   <!DOCTYPE html>
   <html>
   <head>
   <title>Welcome to nginx!</title>
   <style>
   html { color-scheme: light dark; }
   body { width: 35em; margin: 0 auto;
   font-family: Tahoma, Verdana, Arial, sans-serif; }
   </style>
   </head>
   <body>
   <h1>Welcome to nginx!</h1>
   <p>If you see this page, the nginx web server is successfully installed and
   working. Further configuration is required.</p>

   <p>For online documentation and support please refer to
   <a href="http://nginx.org/">nginx.org</a>.<br/>
   Commercial support is available at
   <a href="http://nginx.com/">nginx.com</a>.</p>

   <p><em>Thank you for using nginx.</em></p>
   </body>
   </html>
   EOF

Exit the pod:
```
   exit
```

Verify access to the NGINX welcome page

Get the public IP address of the SLB instance: Expected output:

   kubectl get svc

   NAME            TYPE           CLUSTER-IP        EXTERNAL-IP      PORT(S)        AGE
   nginx-default   LoadBalancer   192.168.XX.XX     47.115.XX.XX     80:30989/TCP   20h

Open the public IP address (for example, 47.115.XX.XX) in a browser. The NGINX welcome page appears.

Step 2: Delete a file and restore it from the Recycle Bin

Simulate data loss by deleting index.html, then restore the file through the Recycle Bin in the ACK console.

Delete the file

Delete the index.html file from the pod:

   kubectl exec cnfs-nas-deployment-597bc9fb45-cmkss -- rm -rf /app/index.html

Refresh the browser. The NGINX welcome page is no longer accessible and a 403 error appears.

Restore the file from the Recycle Bin

The Recycle Bin is enabled by default for NAS file systems managed by CNFS.

Log on to the ACK console. In the left-side navigation pane, click Clusters.
On the Clusters page, find your cluster and click its name. In the left-side pane, choose Volumes > Persistent Volumes.
On the Persistent Volumes page, find the persistent volume (PV) and click Recycle Bin in the Actions column. In this example, the PV name is nas-ecaf6018-5250-4e19-b570-5d9e657d23bc.
On the Recycle Bin tab of the NAS file system page, click the Deleted Files and Directories tab. Find the deleted file and click Restore in the Actions column.
Click Restore to the original path, and then click OK.
Refresh the browser. The NGINX welcome page appears again, which confirms that index.html has been restored.

References

For more information about the NAS Recycle Bin feature, see Recycle bin.